Set-theoretic geology

A ground of the universe V is a transitive proper class , such that and V is obtained by set forcing over W, so that for some W-generic filter . The model V satisfies the ground axiom GA if there are no such W properly contained in V. The model W is a bedrock of V if W is a ground of V and satisfi...

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Main Authors: Fuchs, G, Hamkins, J, Reitz, J
Formato: Journal article
Idioma:English
Publicado: Elsevier 2014
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author Fuchs, G
Hamkins, J
Reitz, J
author_facet Fuchs, G
Hamkins, J
Reitz, J
author_sort Fuchs, G
collection OXFORD
description A ground of the universe V is a transitive proper class , such that and V is obtained by set forcing over W, so that for some W-generic filter . The model V satisfies the ground axiom GA if there are no such W properly contained in V. The model W is a bedrock of V if W is a ground of V and satisfies the ground axiom. The mantle of V is the intersection of all grounds of V. The generic mantle of V is the intersection of all grounds of all set-forcing extensions of V. The generic HOD, written gHOD, is the intersection of all HODs of all set-forcing extensions. The generic HOD is always a model of ZFC, and the generic mantle is always a model of ZF. Every model of ZFC is the mantle and generic mantle of another model of ZFC. We prove this theorem while also controlling the HOD of the final model, as well as the generic HOD. Iteratively taking the mantle penetrates down through the inner mantles to what we call the outer core, what remains when all outer layers of forcing have been stripped away. Many fundamental questions remain open.
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spelling oxford-uuid:a82a9d08-d91c-4ee2-b0e5-f8b5279f30a12022-03-27T02:59:33ZSet-theoretic geologyJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:a82a9d08-d91c-4ee2-b0e5-f8b5279f30a1EnglishSymplectic Elements at OxfordElsevier2014Fuchs, GHamkins, JReitz, JA ground of the universe V is a transitive proper class , such that and V is obtained by set forcing over W, so that for some W-generic filter . The model V satisfies the ground axiom GA if there are no such W properly contained in V. The model W is a bedrock of V if W is a ground of V and satisfies the ground axiom. The mantle of V is the intersection of all grounds of V. The generic mantle of V is the intersection of all grounds of all set-forcing extensions of V. The generic HOD, written gHOD, is the intersection of all HODs of all set-forcing extensions. The generic HOD is always a model of ZFC, and the generic mantle is always a model of ZF. Every model of ZFC is the mantle and generic mantle of another model of ZFC. We prove this theorem while also controlling the HOD of the final model, as well as the generic HOD. Iteratively taking the mantle penetrates down through the inner mantles to what we call the outer core, what remains when all outer layers of forcing have been stripped away. Many fundamental questions remain open.
spellingShingle Fuchs, G
Hamkins, J
Reitz, J
Set-theoretic geology
title Set-theoretic geology
title_full Set-theoretic geology
title_fullStr Set-theoretic geology
title_full_unstemmed Set-theoretic geology
title_short Set-theoretic geology
title_sort set theoretic geology
work_keys_str_mv AT fuchsg settheoreticgeology
AT hamkinsj settheoreticgeology
AT reitzj settheoreticgeology